Seal assembly



Jan. 2, 1951 M. T. WORKS 2,536,898

SEAL ASSEMBLY Filed Aug. 22, 1947 V MADDEN IT. WORKS INVENTOR ATTORNEYS Patented Jan. 2, 1951 UNITED SEAL ASSEMBLY iMadden T. .Works, Houston, "Tex., assignor to Cameron Iron Works, Houston, Tex., a corporation-of Texas Application Aug'ust 22, 1947, Serial No. 770,011

'8"Olaims. 1

This invention relates to seal assemblies and particularly to seal assemblies which may be employed in connection with casing heads, casing and other equipment employed at the tops of Wells. The general object of this invention is to' provide an improved seal assembly of the type referred to-w-hich will not occupy substantially more room than the conventional type of easing head or tubing head and which will provide a seal between such casing or tubing head and a pipe passing therethrough, as Well as suspend such pipe.

It is a more specific object of this invention to provide a relatively simple, compact, inexpensive seal assembly of the type referred to in which the formation of a seal between the pipe hanger and the well head will be assisted by the weight of the pipe suspended on the pipe hanger.

Another object of this invention is to provide a seal assembly of the type referred to in which the pipe hanger has separate means for suspending the pipe and for forming a seal about the pipe,

Another object of this invention isto provide a seal assembly of the type referred to in which separate seals are provided between the pipe hanger and the pipe to be suspended therein and between the pipe hanger and the well head, and in which sufiicient pressure to actuate such seals may .be applied simultaneously from the exterior of the assembly.

Another object of this invention is to provide a seal assembly of the type referred to in which a seal-is provided between the pipe hanger and a pipepassing therethrough and in which additional; pressure may be applied to suchtseal to render it more effective by means accessible from the exterior of the assembly.

Other objects and advantages of this invention will become apparent from the following description and the accompanying drawing wherein is shown by way of illustration and example but not by wayof limitation, one embodiment of this invention.

In the drawing:

The single figure is a View partly in side elevation and partly in vertical cross sectionshowing' a sealassembly constructed in accordance with this invention, secured to the upper end of a well surface casing and surrounding and forming a'seal about .a:well casing, and having secured to its upper end a bonnet Or other fitting "forming a part of the usual Christmas tree assembl of a well.

Referring now more in detail tothe drawings, the casing head I is secured by-means' of threads the usual side flow o-penmgs 9 and as having an 2 or other suitable connection to theupperend of. a surface casingS of a well. Extending lupwardly through the casing head i is a well casing 4 and secured to the upper end of the casing head I by means of studs 5 or the like is the flanged ofv a bonnet or other equipment to be employed above the casing head. This flange isseale'd to the flange 1 at the upper endof the casing head by means of a conventional metal seal ring-.8.

.It will be understood that while the parts [,3 and 4 have been referred to as a casinghead, a surface casing and a well casing, this invention is not limited to such application but the element I on a smaller scale might serveas a tubing head in which event the pipe 3 would represent. a Well casing and the pipe 4 a well tubing. Theterm Well head is employed in this specification and the appended claims as agenerictdesignation includingcasing heads and tubing heads.

The wellhead which is illustrated as havin interiorsurface including an upper zone l0 and a lower zone II. both of which are substantially cylindrical, and. an upwardly facing shoulder l2 between and joining such cylindrical zones.

VAt onevpoint of its circumference theifiange I is provided with a bore 8 3 leading from itsoutermcstsurface and provided with a threaded plug I4. This bore 13 is of such a diameter that it may be said to provide a reservoir for a purpose presently tobe set forth. Leading from its inner end so .as to connect this reservoir with the interior of the well. head at a point a suitable dis tance above the shoulder I2 is a passage l5 of a diameter somewhat smaller than the diameter of the reservoir I3.

Positioned Within the well head i between it and thepipe 4 is a hanger member is which is of annular form. This hangermernber .86 J5 adapted'to fit within the well head i and has external substantially cylindrical surfaces I7 and I8 which are of such diameter as to provide sliding fits respectively within the internal cylindrical surfaces l6 and l l of the well head. These cylindrical surfaces ll .and I8 are joined .,by..a downwardly facing shoulder it which, whenvthe hanger member H5 is within the well head. I will beopposed'to and spaced from the shoulder'lz within the well head. This obviously provides an, intermediate zone between the well head and therhanger in which these two parts are spaced from each other to provide an annular chamber. Two annular sealing members 2! and 22, .1'es pec tively, are located within this chamber adjacent its. upperand lower ends and preferably inengagement with the shoulders l9 and I2. In between these two annular sealing members is a skeleton type spacer ring 23 whereby downward force which may be applied for example to the sealing member 2| may be transmitted to the sealin member 22, and whereby a space is created and maintained between these two sealing members which space is capable of receiving and containing a fiowable pressure applying material by which the sealing members may, if desired, be forced into tighter sealing engagement with the hanger and well head, respectively. It is to be noted that the passage l5 in the well head is so located that when the hanger is in its normal position as illustrated in the drawing, the inner end of this passage I5 will open into the space provided by the spacer ring 23.

The hanger I6 is also provided on its inner surface with an inwardly opening groove 2% in which is located a distortable annular sealing member 25, and the hanger is provided with a passage 26 extending from the space provided by the spacer ring 23 into the bottom of the groove 2 It will be seen that filling the reservoir E3 with a material which is flowable under pressure and then by inserting the plug 14 into the outer end of this reservoir and tightening the same, the material flowable under pressure will be forced from the reservoir [3 through the passage [5 and into the space provided by the spacer ring 23. Thence it will be made to flow through the passage 28 and into the groove 2 behind the sealing member 25. Further tightening of the plug IE will cause a hydraulic pressure to be applied to each of the sealing rings 25, 22 and 25 in a direction to urge them into tighter sealing engagement so that even after the device has been assembled the sealing engagement provided by each of the three sealing rings may be intensified by merely tightening of the plug I4. Thus, any leaks which might appear between the well head I and the hanger It or between the hanger i6 and the pipe l may be stopped by the application of additional pressure.

The hanger i5 is also provided below the groove 2 with a slip receiving groove or bowl having a tapered surface 2! adapted to receive slips 28 for engagement with the pipe i to suspend the same. It will be readily seen that weight suspended by these slips will be transmitted to the hanger l5 pulling downwardly on this hanger and providing for the application of sealing pressure to the sealing members 2! and 22 entirely without regard to the application of fluid pressure to these rings through the tightening of the plug It.

In the practice of this invention it will be understood that the well head I, if the same be a casing head, will be first mounted upon the surface casing 3. Then when it is desired to run the well casing and suspend and seal the same in the well, the well casing will be lowered into the well and cemented in place in the usual manner. Thereupon the hanger it will be placed over the upper end of the casing with the slips 28 in place therein and with the seal rings 55, 22 and 25 and the spacer ring 23 in the proper positions as indicated. The proper amount of strain will be placed on the well casing and then released whereupon the weight of the casing and the strain thereon will be transmitted through the slips 28 to the hanger It; This will tend to move the hanger l6 downwardly and through the coaction of the shoulders 89 and i2 and of the spacer ring 23 will place pressure upon the sealing members 2| and 22 forcing them into tight sealing engagement with the hanger and well head.

The upper end of the well casing will then be cut on at an appropriate level as indicated and the bonnet or other equipment placed on top of the well head and secured thereto by means such as the studs 5.

The plug I4 will then be removed and the reservoir l3 filled with a plastic or fiowable material such as heavy grease with asbestos fibers therein, whereupon the plug will be replaced and tightened, forcing this material under pressure through the passages l5 and 26 so that it will act upon sealing rings 21, 22 and 25. This will not only urge the sealing rings 2| and 22 more tightly into sealing engagement with the well head and hanger but will move the seal ring 25 into sealing engagement about the well casing 4, preventing leakage along the outside of the well casing through the hanger.

From the foregoing it will be seen that by the structure illustrated and described there has been provided a device which is capable of carrying out and accomplishing all of the objects and advantages sought by this invention.

Having described my invention, I claim:

1. In combination, an annular well head having on its inner surface upper and lower cylindrical zones joined by an upwardly facing shoulder, an annular hanger having on its outer surface upper and lower cylindrical zones of diam-' eters to fit within said zones in the well head re-,

spectively and joined by a downwardly facing shoulder, said hanger having an inwardly open groove in its inner surface, a pair of annular distortabl sealing members between said shoulders, a skeleton type spacer ring between said sealing members, an annular distortable sealing member in said groove, said hanger and head having communicating passages therein connecting the exterior of said head with the space between said eters to fit within said zones in the well head respectively and joined by a downwardly facing shoulder, said hanger having an inwardly open groove in its inner surface, a pair of annular distortable sealing members between said shoulders, a skeleton type spacer ring between said sealing members, an annular distortable sealing member in said groove, said well head having a reservoir formed in one side thereof and said head and hanger having registering passages therein connecting said reservoir with the space between said first two sealing members and with the bottom of said groove, and means for forcing a fiOW- able material under pressure through said passages and into the space between said first mentioned distortable member and into said groove behind the distortable sealing member therein.

3. In combination, an annular well head having on its inner surface upper and lower cylin-' drical zones joined by an upwardly facing shoulder, an annular hanger having on its outer surface upper and lower cylindrical zones of diameters to fit within said zones in the well head respectively and joined by a downwardly facing shoulder, said hanger having an inwardly open groove in its inner surface, a pair of annular distortable sealing members between said shoulders, a skeleton type spacer ring between said sealing members, an annular distortable sealing member in said groove, said well head and hanger having passages therein providing communication between the exterior of said head and the space between said first two sealing members and with the bottom of said groove, means for forcing a flowable material under pressure through said passages and into the space between said first mentioned distortable sealing members and into said groove behind the distortable sealing member therein, and pipe suspending means carried by said hanger for suspending a pipe therein.

4. In combination, an interfitting annular well head and annular hanger having intermediate registering zones with adjacent surfaces of different diameters to provide an annular space between them, a pair of annular distortable sealing members in said space adjacent the opposite ends thereof respectively, said hanger having an inwardly opening groove in its inner surface, a third annular distortable sealing member therein, and means for forcing a flowable material under pressure into the groove behind said third sealing member. i

5. In combination, an interfitting annular well head and annular hanger having intermediate registering zones with adjacent surfaces of different diameters to provide an annular space between them, a pair of annular distortable sealing members in said space adjacent the opposite ends thereof respectively, said hanger having an inwardly opening groove in its inner surface, a third annular distortable sealing means therein, and means for forcing a fiowable material under pressure between said first mentioned sealing members and into the groove behind said third sealing member.

6. A pipe hanger comprising an annular member having its inner surface formed with an annular inwardly opening packing receiving groove and an annular inwardly opening slip receiving groove, the bottom of slip receiving groove being tapered, and having its outer surface formed with upper and lower substantially cylindrical zones and a downwardly facing shoulder between them.

7. In combination, a well head, a hanger located therein, spaced distortable sealing members between said head and hanger, said hanger having a groove in its inner surface, a distortable sealing member in said groove, and a common means for supplying flowable material under pressure to all three of said distortable sealing members to move them'toward sealing position.

8. A pipe hanger comprising an annular member having its inner surface formed with an annular inwardly opening packing receiving groove and an annular inwardly opening slip receiving groove, the bottom of slip receiving groove'being tapered, and having its outer surface formed with upper and lower substantially cylindrical zones and a downwardly facing shoulder between them and a passage formed in the annular member communicating between the packing receiving groove and the outer periphery of the member at the smallest diameter of one of the cylindrical zones.

MADDEN T. WORKS.

REFERENCES CITED Name Date Allen June 29, 1948 Number 

